Ghazoul Jaboury
Department of Environmental Sciences, Imperial College London, Silwood Park, Ascot, Berks SL5 7PT, UK.
Biol Rev Camb Philos Soc. 2005 Aug;80(3):413-43. doi: 10.1017/s1464793105006731.
The ecological significance of spacing among plants in contributing to the maintenance of species richness, particularly in tropical forests, has received considerable attention that has largely focussed on distance- and density-dependent seed and seedling mortality. More recently it has become apparent that plant spacing is also relevant to pollination, which often constrains seed production. While seed and seedling survival is reduced at high conspecific densities, pollination success, by contrast, is positively correlated to local conspecific density. Distance-dependent mechanisms acting on pollination and seed production have now been described for a variety of plants, with relatively isolated plants or fragmented populations generally suffering reduced fecundity due to pollen limitation. Yet there is considerable variability in the vulnerability of plant species to pollination failure, which may be a function of breeding system, life history, the pollination vector, the degree of specialisation among plants and their pollinators, and other indirect effects of habitat change acting on plants or pollinators. As reduced tree densities and population fragmentation are common outcomes of anthropogenically altered landscapes, understanding how pollination processes are affected in such degraded landscapes can inform effective conservation and management of remaining natural areas.
植物间距对维持物种丰富度的生态意义，尤其是在热带森林中，已受到相当多的关注，这些关注主要集中在距离和密度依赖性的种子及幼苗死亡率上。最近，很明显植物间距也与授粉相关，而授粉往往会限制种子产量。虽然在高同种密度下种子和幼苗的存活率会降低，但相比之下，授粉成功率与当地同种密度呈正相关。现在已经描述了多种植物中作用于授粉和种子生产的距离依赖性机制，相对孤立的植物或碎片化种群通常由于花粉限制而繁殖力降低。然而，植物物种对授粉失败的脆弱性存在很大差异，这可能是繁殖系统、生活史、授粉媒介、植物与其授粉者之间的专业化程度以及栖息地变化对植物或授粉者的其他间接影响的函数。由于树木密度降低和种群碎片化是人为改变景观的常见结果，了解在这种退化景观中授粉过程如何受到影响可以为有效保护和管理剩余自然区域提供信息。
